AT&T iPhone 4S Tops Verizon, Sprint on Data Speeds, Web Browsing

With the iPhone 4S now available on three of the four major U.S. carriers, which one is your best option? In a report released Friday, Metrico Wireless found that while each provider has its benefits, AT&T edges out Sprint and Verizon when it comes to speed.

In the wake of the iPhone 4S launch last month, Metrico ran tests on the device across the AT&T, Verizon, and Sprint networks to measure: call performance; voice quality; data performance; Web browsing; and video performance. In all, Metrico performed more than 21,000 Web page downloads, 8,000 data download and upload tests, and made about 6,000 voice calls.

What did they find? While Verizon continued to surpass its rivals in terms of placing calls and maintaining a connection, AT&T was tops when it came to download and upload speeds, as well as Web browsing.

"The AT&T iPhone 4S outperforms its Verizon and Sprint counterparts in data download and upload speeds," Metrico found. "Moreover, the AT&T iPhone 4S outperforms the iPhone 4 in download speeds by a considerable margin." Web browsing was also faster on AT&T.

When it comes to placing calls, however, success rates were "slightly better" on Verizon than AT&T and Sprint. "Sprint's iPhone 4S performs better than the other carriers in live network voice quality on the uplink, while AT&T's iPhone 4S takes the lead in live network voice quality on the downlink," Metrico said. "However, the two carriers' results are comparable."

Overall, the "iPhone 4S outperforms more than 70 percent of competing 3G Smartphone models tested on the three networks," Metrico found. The iPhone 4S is tops for "speech quality in noise; average in speech quality over Bluetooth; and a below average performer in speakerphone speech quality."

The iPhone 4S also demonstrated excellent data task reliability, or the ability to complete a task. It achieved 100 percent or almost 100 percent success rates when it came to stationary downloads, stationary uploads, and Web page loads.

"The improvement gains in stationary download reliability over the iPhone 4 are dramatic for AT&T and Verizon," Metrico said.

"When on the live network and playing a video clip through the web browser, the iPhone 4S showed comparable, high rates of video frame delivery across all three carriers," the company continued. "However, when playing a video clip through YouTube, video frame delivery rate dropped, although the subscriber is still likely to perceive good quality. In general, the iPhone 4S shows a very low rate of video freezes and impairments, and a very high rate of audio delivery, across the three carriers' networks."